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dewey2011
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Posted: 11/20/2011 8:57:50 AM
I'm a newbie....but have been unable to find a thread on reducing pre-travel. I've done a modest trigger job and replaced springs with JP yellows, pull about 4# now which is fine.

Thanks for your help-dan
pappy177
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Posted: 11/20/2011 9:22:55 AM
"Those who hammer their guns into plows, will plow for those who do not." Thomas Jefferson"
Dano523
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Posted: 11/20/2011 9:23:38 AM
[Last Edit: 11/20/2011 11:55:33 AM by Dano523]
Without going buck wild, there is a quick way to remove a great deal of pre-creep from a single stage trigger.


Set the selector to safe, re cock the action, now cheek to see how much travel you have on the trigger from rest until it maxes out against the selector (read hammer can not release since the selector has it blocked, but you still have trigger travel from at rest to against the selector). It's this travel that you can remove safely without worries. having mod any of the FCG parts.


The option are to buy a new pistol grip set screw that has the inner adjustable screw on it, or to just buy a 1/4"-28 pitch, 1/4" long allen set screw, and shorten the pistol grip screw by 3/8".

Since the set screw screw is the cheaper option, let just talk about it.

With the grip, and FCG removed for starters, you going to insert the small set screw up the threads of the receiver until you have about half of the threads above the bottom of the receiver. Apply a light coat of Blue loctite to the exposed threads of the small set screw, then screw it back down the channel until the top of it is flush with the bottom of the receiver void. Now reinstall the FCG inner workings, then with the selector set to safe, and the selector detent pin in the channel and using a small punch to push up on the detent so it centers out the selector on safe (detent tight in the selector groove for it), go back and now tighten the set screw upwards until turning the selector from safe to fire takes a slight more pressure than normal.
Note, the selector to back of trigger will slightly wear-in quickly, so go for the tighter side to begin with, instead of on the lighter side to turn the selector, and having to go back in later to readjust the set screw.

What is happening is the tip of the set screw is pushing the back of the trigger upwards, removing all that extra creep that is not needed.

As for the pistol grip screw, again, it needs to be shorten about 3/8" so when it is installed, it does not max out against the new installed set screw up the channel above it.

As for the other screw, pretty much adjusted the same way, but since there is an small inner set screw through the standard pistol grip screw, you can adjust the creep out with the pistol grip/screw in place.

http://www.brownells.com/.aspx/pid=307/Product/AR-15-M16-DROP-IN-TRIGGER-ADJUSTER


As for going for no creep at all (read bench rest type trigger),then you need to shim both the trigger and hammer to remove unneeded side ways move of both so you can perfectly match the seats to each other square, reset the sears, and even re-time the disco as well (read not for the novice, but I have a few of my bench rest/long range AR triggers set this way down to under the 2lb marks). Also to note, when doing a trigger this way, the smith will need the entire rifle since the trigger has to be set to that specific receiver.


Posted By PlaymoreMinds:

'Twas not the <cough> sweet and innocent <cough> PlaymoreMinds...

<---skips away in frilly skirts to Candyland, leaving gutters and snorkels FAR behind.
Dano523
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Posted: 11/20/2011 9:29:46 AM
[Last Edit: 11/20/2011 9:30:20 AM by Dano523]
Originally Posted By pappy177:
This has helped some


DON'T CLIP THE END OF THE TRIGGER SPRING LEG!!!!!!!!!!!!!!!!!!!!!

If you want to reduce spring tension, you can tweak the spring legs at the end of the coils. Bending the spring legs after the coil is going to cause the spring legs to come out of the trigger pin annular groove as you pull the trigger. With the spring legs tweaked at the coils to reduce tension, then the relationship of the legs to the trigger pin annular grooves stay the same, and the legs are not lifted out of the pin grooves via the end of C channel on the trigger as it being pulled.

To also note, with a reduce hammer spring, you better make sure that your FP protrusion is close to the max range of .037, and even more so if you are using a reduced weight speed hammer as well (to maintain reliable ignitions).

Posted By PlaymoreMinds:

'Twas not the <cough> sweet and innocent <cough> PlaymoreMinds...

<---skips away in frilly skirts to Candyland, leaving gutters and snorkels FAR behind.
dewey2011
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Posted: 11/20/2011 10:07:16 AM
[Last Edit: 11/20/2011 10:08:26 AM by dewey2011]
I should have mentioned it's a standard DPMS trigger/hammer group. Like I said I put in JP yellow springs and don't plan on fooling with them.
Thanks for all the guick replies ! dan
madcratebuilder
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Posted: 11/20/2011 11:37:29 AM
If the grip screw hole on the lower is threaded all the way through just install a set screw to adjust out the creep. Figure out were you want it and then add some loc-tite. If your lower is not thread just run a tap through tit. This is a quick and easy mod. Good choice not to cut or bend your new springs.
Schleprock
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Posted: 11/20/2011 12:13:53 PM

$44 for a machine screw, a set screw and an Allen wrench??? OMG!!!

I would make and sell those all day long for only $20 each...

LOL!
Dano523
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Posted: 11/20/2011 6:23:25 PM
Originally Posted By Schleprock:

$44 for a machine screw, a set screw and an Allen wrench??? OMG!!!

I would make and sell those all day long for only $20 each...

LOL!


Kind of the going price to rework a threaded bolt.

Take the adjustable gas port systems for the Garand,

You have to anneal the standard cylinder bolt so it workable, then drill and tap it, then either set it up for a single set screw, or drill a few smaller allen bolts for bolts, then heat treat the whole mess back up when your done.

By the time you throw in the manufacturers cost, over head, and shipping to the reseller, , then the resellers mark up as well, your around the $40 dollar mark up at the end for a product that is just a few cents on the dollar with labor thrown in to begin with.

http://www.brownells.com/.aspx/cid=0/k=garand%20adjustable%20gas/t=P/ksubmit=y/Products/All/search=garand%20adjustable%20gas

Posted By PlaymoreMinds:

'Twas not the <cough> sweet and innocent <cough> PlaymoreMinds...

<---skips away in frilly skirts to Candyland, leaving gutters and snorkels FAR behind.
RacingJake
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Posted: 1/3/2012 7:40:13 PM
[Last Edit: 1/3/2012 7:45:10 PM by RacingJake]
I made a set screw from a 1/4 bolt with 28 teeth and cut a slot for a screwdriver, also did alittle bending on my stock hammer spring and the end still sits on top of the trigger retaining pin.

Works good with no creep and trigger pull is a hair under 5 lbs now, which is prefect for me and didn't cost a dime.


Dano523
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Posted: 1/4/2012 1:40:46 AM
[Last Edit: 1/4/2012 1:41:39 AM by Dano523]
Originally Posted By RacingJake:
I made a set screw from a 1/4 bolt with 28 teeth and cut a slot for a screwdriver, also did alittle bending on my stock hammer spring and the end still sits on top of the trigger retaining pin.

Works good with no creep and trigger pull is a hair under 5 lbs now, which is prefect for me and didn't cost a dime.


http://i273.photobucket.com/albums/jj208/Racingjake/101_1641.jpg


You bent the spring in the wrong area. If you are going to tweak a spring, do so at the coils so the leg still comes out straight off the coils.

With your spring bent in the legs, the trigger side C channel is going to walk the trigger leg up out of the pin annular groove when the trigger is pulled; with the trigger pin just walking out of the receiver over time.

Posted By PlaymoreMinds:

'Twas not the <cough> sweet and innocent <cough> PlaymoreMinds...

<---skips away in frilly skirts to Candyland, leaving gutters and snorkels FAR behind.
RacingJake
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Posted: 1/4/2012 12:46:38 PM
[Last Edit: 1/4/2012 12:53:12 PM by RacingJake]
The end of the spring still engages the groove on the trigger pin with the trigger pulled or at rest, hard to tell from the pic. I got over 400 rounds through it and the trigger pin will not walk out. I still get that little pop when you try to break it free by pushing on it.

I like your idea too, only one bend compared to my two